Field of the Invention
The present invention relates to an image pickup apparatus which obtains the two-dimensional intensity distribution of light and angle information of light rays in an object space and an image processing apparatus which generates a reconstructed image from images obtained by such an image pickup apparatus.
Description of the Related Art
In recent years, there have been proposed image pickup apparatuses which perform an operation on data obtained by an image pickup element and perform digital image processing according to the resulting data, thereby outputting various images. The literature of “Ren Ng, et al., “Light Field Photography with a Hand-held Plenoptic Camera”, 2005 Computer Science Technical Report CTSR” discloses an image pickup apparatus which obtains the two-dimensional intensity distribution of light and angle information of light rays in an object space at the same time using “Light Field Photography”. Here, the two-dimensional intensity distribution of light and angle information of light rays are together called a light field, and three-dimensional information in the object space can be obtained by obtaining the light field. In such an image pickup apparatus, it is possible to obtain the light field and, after the image is shot, to perform image processing, thereby changing (adjusting) the focus position, photographing viewpoint, depth of field, etc., of an image, called refocus.
Meanwhile, as to photograph expressions, ones where the main object stands out by intentionally blurring the foreground and background in portrait photography and macro photography of a flower, an insect, etc., are preferred. When aiming for such a photograph expression, in order to obtain a beautiful background blur, the object is often photographed with an image pickup apparatus having a shallow depth of field. However, while a beautiful background blur is obtained using a lens having a shallow depth of field, if the object itself has a depth, the entire object cannot be photographed clearly, resulting in part of the object being blurred. If the object is photographed with a deeper depth of field in order to prevent this, a beautiful blur is not obtained. As such, with conventional image pickup apparatuses, the background blur and depth of field cannot be controlled independently.
Japanese Patent Laid-open No. 2011-211523 discloses a configuration where with changing the focus position, a plurality of images are shot, thereby performing a blur control.
However, in the configuration of Japanese Patent Laid-open No. 2011-211523, a plurality of images need to be picked up, and hence, for example, when a fast moving object such as an insect is photographed, because of the differences in a shooting time between the plurality of images, the positions of the moving object included respectively in the plurality of images are different. Thus, it may be difficult to perform blur control using a plurality of shot images.